Watertight and air pervious flocked sheet material and method of making same



Aug. 9, 1955 P. HlRscHBl-:RGER 2,715,074

WATERTIGHT AND AIR PERVIOUS FLOCKED SHEET MATERIAL AND METHOD OF' MAKING SAME Filed May 22. 1952 INVENTOR PA UL H/RSHBEHGER BY @TQM ATTORNEY United States Patent ce 2,715,074 Patented Aug. 9, 1955 AWATERTIGHT AND ATR PERVIOUS FLOCKED SHEET MATERIAL AND METHOD F MAK- ING SAME Paul Hirscliberger, Paris, France, assigner to Society Palladium, Argenteuil, France, a corporation of France Appiicatio May 22, 1952, serial N0.289,44o Claims priority, application France January 30, 1952 11 Claims. (Cl. 117-17) The present invention relates to a flocked fabric or suede fabric wherein short natural or articial textile fibers are anchored by an adhesive layer carried on the face of a fabric web to provide material resembling velvet, buckskin and similar products.

i An object of the invention is to provide, on the one hand a material that wears very well, and does not lose `forming the adhesive layer.

The thickness of the rubber layer is selected so as to surround the implanted fibres over about one-tliird of their length.

According to the manufacturing process, which is also A `to the backing fabric so that friction or folding can not result in dragging away the fibres..` Due to the fact that the fibres cross through the rubber layer without being ineness of these channels prevent water from flowing through and their very large quantity (the fibres density can reach and even exceed 40,000 per square centimeter) allows a free passing of the air. This air permeability permits use of the fabric according to the invention for invention will confer elasticity, feeL strength and the 4look of a velvet fabric, leather or a high grade skin.

thread towhi'ch` the Hocking process according to the i 30 T this layer without being impregnated with the substance wherein several embodiments of the invention are illustrated.

In the drawing: i

Fig. l is a diagrammatic side elevational view of apparatus for applying an anchoring layer and the Hock to a fabric backing. i

The strip of backing fabric 10 is continuously fitted The strip is driven, in a known way over rotating cylinders 11 and the layer of rubber is spread on its upper face by means of a doctor-blade 12 and of the rubber layer 22 (Fig. 2). After passing over the heating plates 16 and the rubber being dried, the fabric is moved into a tunnel dryer 21 having a temperature of about C., in which the rubber is cured in a few minutes.

water cannot get in.

According to a second embodiment, the layer consists many, a suiicient throughfare for the air. then dried. A new layer of rubber is spread over it, the

fibres are implanted in this last layer and the whole is cured, the adhesiveness between the two layers with a foundation of rubber resulting in the formation of a very solid flock fabric.

The granular adhesive product according to the second embodiment for the intermediate adhesive layer spread on the backing fabric is constituted by an aqueous paste of a body containing some synthetic or natural rubber, coagulated but non cured, in the form of thin and fairly spherical particles, resembling fish eggs.

When this paste has been spread on the fabric with a thickness of about one-tenth of millimeter and has been cured the spherical granules, juxtaposed and adhering to each other, which form this layer after the evaporation of the water, offer countless apertures through which the air fiows easily, as it has been shown from experience. These apertures are too small to let the water go through.

The process, according to the invention, of preparing the granular paste above described consists in preparing a foam with a crude natural or synthetic rubber, foam `at a temperature lower than the cure temperature and crushing it to obtain substantially spherical particles, of a size of about .0l to 0.15 millimeter.

The adhesive paste according to the invention is made preferably of latex. formation, or autovulcanization, of the latex coagulated in the shape of granules, it is advisable to add to the mixture a given amount ofl gutta-percha.

To this gutta-percha are first added about of stearic acid and of sodium oleate. The mixture is subjected to a strong mastication between cylinders heated at about 60 C. After cooling, the mixture is crushed anew in the cold state and the resulting fragments are treated during one hour, at 165 C., with hot air in a closed chamber, this thermic treatment being intended to soften the gutta-percha and to make it absorb water. The mixture is then kneaded with hot water, giving a paste which can be mixed with the latex.

One makes then the following mixture:

Parts Concentrated latex to 60% 330 Gutta-percha paste 110 Accelerating products 5 Zinc oxide 7 Lithopone at 60% 8 Emulsion stabilizer 3 Sal ammoniac 10 Colloidal sulfur 4 The mixture is beaten for a few minutes, under a stream of compressed air, to form a foam which is coagulated by an addition of silicon fluoride in becomes solid and is at the utmost. The product obtained has a cellular structure and is crushed between two rolls turning at a slow speed. The result is a granulated product consisting of spherical particles, having a diameter of about 0.1 to 0.15 millimeter and made of a coagulated mixture of latex and gutta-percha. This granulated product can at any moment be mixed with water to provide a paste which is adhesive and can be cured.

To prevent an excessive desiccation of the granulated product when stored and to permit thinning water to be added just before use, the latex granules are embedded in a sheltering film 0f Turkey redoil mixed with the product at a rate of about 1.5% and which, when used, will emulsify very easily with the thinning water.

This adhesive granular paste is spread on the fabric in a known way, for instance by means of a doctor blade spreading the paste over the fabric which is driven through the machine at a speed of 2 meters per minute for instance. The thickness of the paste layer should preferably be about 0.15 millimeter. In order to increase the adhesiveness, the machine is slightly heated.

The coated fabric is dried and afterwards coated with drying this f However, to prevent the slow transthe layer in which the fibers are implanted and the whole assembly is cured, thus producing an excellent adhesiveness between the backing fabric and the granular layer, on the one hand and between this granular layer and the layer bearing the flock fibers on the other hand.

The appearance of the finished fabric may be varied by employing fibers of various type such as rayon, cotton, wool, and the like. The length of the fibers may also be varied between 0.5 and 5 millimeters. The thickness of the rubber layer or layers may be varied'accordingly.

What l claim is:

l. A watertight and air pervious flocked sheet material comprising, a base fabric, a layer of exible binding material covering one face of said fabric and adhering thereto, said layer having a multitude of tiny apertures therethrough providing for the passage of air only through said layer, a second layer of liexible binder impervious material covering an outer face of the first layer and adhering thereto, a multitude of fibers with their inner ends extending through the second layer and perpendicular thereto, and the material of the second layer surrounding and anchoring inner end portions of the fibers -without impregnating the fibers to any substantial extent.

2. A watertight and air pervious flocked sheet material comprising, a base fabric, a layer of flexible binder material covering one face of said fabric and adhering thereto, said layer having a multitude of juxtaposed tiny perforated craters allowing air only to flow through said layer, a second layer of iiexible impervious 'binder material covering an outer face of the first layer and adhering thereto, a multitude of fibers having their inner endsextending through the second layer and perpendicular thereto, and the material of the4 second layer surrounding and anchoring inner end portions of the fibers without impregnating the fibers to any substantial extent.

3. A watertight and air pervious ocked sheet material comprising, a base fabric, an air pervious layer of ilexible binder material covering one face on said fabric and bonded thereto, said layer including a multitude of juxtaposed granular particles providing therebetween tiny apertures allowing air only to iiow transversely through said layer, a second layer of flexible impervious binder material covering an outer face of the first layer and bonded thereto, a multitude of fibers having their inner ends extending through the second layer and perpendicular thereto, and the material of the second layer surrounding and anchoring inner end portions of the fibers without lmpregnating the fibers to any substantial extent.

4. watertight and air pervious flocked sheet material comprising, a web of textile fabric, a layer of flexible binder material covering one face of said fabric and bonded thereto, said layer having a multitude of apertures therethrough providing for the free passage of air through said layer, said apertures being sufficiently small to prevent the passage of water through said layer, a second layer of lmpervious flexible binder material covering an outer face of the first layer and bonded thereto, a multitude of air pervious fibers with inner end portions of the fibers extending perpendicularly through said second layer into the presence of the first layer, and the material of the second layer surrounding and anchoring inner end portions of said fibers without impregnation of the fibers to such an extent which would obstruct air permeability.

5. A method of making a watertight and air pervious flocked sheet material which comprises, coating one face of the base fabric with a layer of fiexible binder material having the characteristics of adhering to the base fabric, forming a multitude of tiny apertures in said layer providing passage therethrough for air, drying said layer, applying a second layer of flexible vulcanizable adhesive material over an outer face of the first layer, projecting fibers onto the second layer with inner end portions of the fibers arranged substantially perpendicular to the second layer and with sufficient force to move inner end portions of the fibers through the second layer into the presence of the first layer, and vulcanizing the adhesive material forming the second layer before impregnation of the inner end portions of the fibers to any substantial extent.

6. A method according to claim 5 wherein the first layer is obtained by coating the base fabric with a relatively thin layer of latex foam and crushing bubbles of the foam layer whereby small craters are formed to provide the tiny apertures.

7. A method according to claim 5 wherein the first layer is obtained by preparing an aqueous paste of a co agulated but non-vulcanized latex having a multitude of substantially spherical particles therein, coating the base fabric with said paste and drying the layer before application of the second layer thereon.

8. A method according to claim 5 wherein the first layer is obtained by preparing an aqueous paste of a mixture of about 25% gutta-percha and 75% latex concentrated up to 60%, coagulating said mixture and reducing the coagulated material to a granular form, coating the base fabric with said material and drying it to elirninate water before the second layer is applied.

9. A method according to claim 5 wherein the first layer is obtained by adding to gutta-percha about of stearic acid and of sodium oleate, masticating the mixture under heat, cooling and further masticating after cooling, treating the mixture with hot air at about 165 C., kneading it with hot water to produce a paste, mixing the paste with three times as much in weight of latex concentrated up to 60%, adding to the mixture accelerating and stabilizing products, beating up the paste to form a foam, coagulating the foam by an addition of silicon fluoride in suspension, drying at about 70 C. and crushing the coagulated foam to reduce it to a finely divided granular state, and mixing the granulated product with water to form an adhesive paste.

10. A method of manufacturing a ocked fabric which comprises, applying a flexible adhesive layer of binder material over one face of a fabric sheet, producing a large number of tiny apertures in Said layer extending therethrough providing for the passage of air through said layer, drying said layer, applying a flexible vulcanizable `layer over an outer face of the first layer of binder material, subjecting the fabric with layers carried thereon and a multitude of fibers to an electrostatic field at a voltage of about 150,000 volts to move the fibers with their lengthwise dimensions substantially perpendicular to the fabric whereby inner end portions of the fibers move transversely through the second layer, and vulcanizing said second layer before the material thereof has had an opportunity to impregnate the fibers to any substantial extent.

11. A process of making a flocked fabric which cornprises, applying a flexible adhesive vulcanizablc material as a layer over one face of a fabric web, said material having a multitude of craters therein with tiny apertures providing communicating passages for air through said layer, allowing said layer to dry, applying a continuous flexible layer of vulcanizable material over an outer face of the first layer, subjecting the fabric with the layers carried thereon and a multitude of fibers to an electrostatic eld at a voltage of about 150,000 volts to move the fibers with their lengthwise dimensions substantially perpendicular to the fabric whereby the inner end portions of the fibers move transversely through the second layer with the inner ends into the presence of the first layer, and vulcanizing the layers before the materials thereof have an opportunity to impregnate the fibers to any substantial extent.

References Cited in the file of this patent UNITED STATES PATENTS 25,192 Goodyear Aug. 23, 1859 2,033,099 Hanley et al Mar. 3, 1936 2,047,525 Thode July 14, 1936 2,096,933 Burgess Oct. 26, 1937 2,140,026 Murphy et al. Dec. 13, 1938 2,187,140 Faris et al Jan. 16, 1940 2,194,036 Talalay Mar. 19, 1940 2,228,735 Spraragen Jan. 14, 1941 2,287,837 Smyser June 30, 1942 2,328,904 Hiers Sept. 7, 1943 2,349,153 Ferrante May 16, 1944 2,358,227 Hiers Sept. 12, 1944 2,395,267 Gilbert Feb. 19, 1946 2,447,374 Smyser Aug. 17, 1948 2,539,931 Rogers et al Ian. 30, 1951 2,567,327 Ewing Sept. 11, 1951 2,592,602 Saks Apr. 15, 1952 

11. A PROCESS OF MAKING A FLOCKED FABRIC WHICH COMPRISES, APPLYING A FLEXIBLE ADHESIVE VULCANIZABLE MATERIAL AS A LAYER OVER ONE FACE OF A FABRIC WEB, SAID MATERIAL HAVING A MULTITUDE OF CRATERS THEREIN WITH TINY APERTURES PROVIDING COMMUNICATING PASSAGES FOR AIR THROUGH SAID LAYER, ALLOWING SAID LAYER TO DRY, APPLYING A CONTINUOUS FLEXIBLE LAYER OF VULCANIZABLE MATERIAL OVER AN OUTER FACE OF THE FIRST LAYER, SUBJECTING THE FABRIC WITH THE LAYERS CARRIED THEREON AND A MULTITUDE OF FIBERS TO AN ELECTROSTATIC FIELD AT A VOLTAGE OF ABOUT 150,000 VOLTS TO MOVE THE FIBERS WITH THEIR LENGTHWISE DIMENSIONS SUBSTANTIALLY PERPENDICULAR TO THE FABRIC WHEREBY THE INNER END PORTIONS OF THE FIBERS MOVE TRANSVERSELY THROUGH THE SECOND LAYER WITH THE INNER ENDS INTO THE PRESENCE OF THE FIRST LAYER, AND VULCANIZING THE LAYERS BEFORE THE MATERIALS THEREOF HAVE AN OPPORTUNITY TO IMPREGNATE THE FIBERS TO ANY SUBSTANTIAL EXTENT. 